import pandas as pd
import numpy as np
a8=np.arange(24).reshape(4,6)
s1=pd.DataFrame(np.random.randint(30,101,size=(10,3)),columns=['语文','数学','英语'],index=map(lambda x:'A'+f'{x:03}',range(1,11)))
print(s1.iloc[4,2])
print(s1.loc['A003':'A008'])
print(s1.query('语文<60 and 数学<60 and 英语<60'))
print(s1[s1['语文']>90])
print(s1[s1['英语'].isin([10*i for i in range(1,11)])])

print(s1.size)
s1['总分']=s1.sum(axis=1)
s1['平均分']=s1['总分']/3
print(s1)
del s1['平均分']
s1.drop(['A005','A010'],axis=0,inplace=True)
print(s1)